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-   -   Cranfield crash, 5 June 2013 (https://www.pprune.org/private-flying/516403-cranfield-crash-5-june-2013-a.html)

Ajruk 15th Jun 2013 20:12

I agree downwind, its nice to see a helpful response. I think the issue here is that he never had an engine failure, he had a partial so he turned back. With a full failure he wouldn't have Im sure.

JPlumridge 15th Jun 2013 20:28

There is definitely lessons to be learn't from this accident, even with a partial engine failure you should pitch down during take-off and start planning for a forced landing in case that is indeed needed.

During my training my instructor would periodically push my hand off the throttle and move it to idle during take-off and I was expected to react swiftly and in the correct manner, this is all in order to drill it into you to make sure you would instinctively choose this option if faced with any problems on climb out.

There was a video uploaded to youtube recently with a partial engine failure on take-off which demonstrated what needs to be done perfectly.

Genghis the Engineer 15th Jun 2013 20:32

I've twice had a partial and turned back, both times the aeroplane was unscratched. One was a plug failure, the other a pump failure. The art, in my opinion is flying field to field whilst keeping speed speed about min drag (~best glide at first approximation), then approach once the landing runway / field is safely achievable.


I've flown with a student - a very low hour UK PPL trained at an overseas school somewhere sunny that I was doing a syndicate checkout for. He believed that a turnback was appropriate in the event of an EFATO, and had clearly been told this by somebody who had trained him - despite his never having practiced it. I assume the instructor at his overseas school, as he had many other bad habits as well, although I didn't ask specifically.

G

mad_jock 15th Jun 2013 20:47

With a partial nothing really changes until you have pitched for the airspeed and choosen a field the carried out engine drills. Then you can look at how much partial performance you have.

Remeber though that as soon as you turn your performance decreases so even a 50ft/min climb will turn quickly into desent the steeper the bank angle.

rob_k31 15th Jun 2013 20:53

In my option, the 'turn-back / land ahead' question is a split second decision for the pilot. If someone's in that position it's easy to puick the wrong option.

If the engine failure was preventable then that is the root cause and the pilot's decision is a lesser factor.

I don't believe the age of the aircraft is an issue. It's how well maintained it is and the quality of parts used etc. A fully overhauled engine is basically a new engine.

Mariner9 15th Jun 2013 20:56


would you turn back with partial power?
That's a difficult question. Personally, I brief for EFATO before every T/O, but have never briefed for partial power. Would be a seat-of the-pants decision therefore, presumably as it was for the handling pilot(s). So maybe yes,maybe no for me.

That said, a turn with partial or even no power should not result in a stall/spin if flown correctly. However, Human factors training tell us that humans will make mistakes, particularly in high stress situations like an EFATO. For that reason I think most or all posters on here sympathise with the pilots concerned, despite the fact the majority view appears to be pilot error.

Ajruk 15th Jun 2013 21:06

Mariner I am an instructor myself and I feel your last comment is very fair. I also would not turn back, though with a partial I would be tempted and may have. There's still no guarantee that a field landing would've been any more successful however.

downwind24 15th Jun 2013 21:24

As an instructor I have practised , in my head at least , engine failures/partial engine failures , at the field I fly from on thousands of occasions.

I almost know every blade of grass within two miles of where I fly from. The slope/gradient/size of every field that is within glide distance after my runway is used.

I also train my students the same so that should it ever happen to them then they know where to go.

Happiness was seeing an EFATO from an examiner on the end of '20' and a right turn while trimming for best glide....'instinctive' was the word used. And it is the only available place to land should it go bang there !

A and C 15th Jun 2013 21:43

The imposable turn.
 
Ajruk.

Since World War One it has been recognized that turning back is the imposable turn and this accident serves only to demonstrate how true this is.

If you want to continue in flying you need to distance yourself from your feelings for your friend ( no matter how noble and loyal they may be) and recognize that the turn back was a mistake, I have no idea how much power the engine in this case was producing ( as have you ) but the only way to get the aircraft away from the ground with a malfunctioning engine is to nail the best lift/ drag speed with the wings level.

If there is no chance of climbing then the only choice is to use the power you have to get to the best into wind landing site. Do this and you load the dice in your faviour, don't and you shorten the odds on a sucsessful outcome are diminished to almost zero.

DLT1939 15th Jun 2013 21:50

In a ten year period to 2000 in Australia, there were 75 reported cases of engine failure in single engined aircraft after takeoff, none of which resulted in fatalaties. In the same period there were 242 reported cases of partial power loss after take off resulting in fatalities in nine cases. The ATSB attribute this considerably worse experience in part to comprehensive coverage of EFATO's in PPL training, but little or none of partial power loss scenarios.

Detail here:

http://www.atsb.gov.au/publications/2010/avoidable-3-ar-2010-055.aspx



x933 15th Jun 2013 22:20

Little to add to this, other than i've recently done some 300ft turnbacks in gliders - with a cross downwind landing there's no way i'd want to attempt it in an aircraft with even more marginal performance, let alone a PA38 deficient some horses.

If you've got "some" power - use it. Another couple of hundred feet might have made a turnback more of a feasible option (As a point of note, way back in time on the RAF G115 Tutors solo students were prohibited from turning back and instructors limits were 500ft (possibly 800ft - the memory fades). And even then i'd probably have taken a punt on using the extra height to try and A) sort the problem B) position for a decent field.

Glad to hear the passengers are on the mend.

mary meagher 15th Jun 2013 22:40

Back when I was still allowed to fly my PA18, a very very crafty instructor gave me my annual check ride. From 1,500 feet about 8 miles away, the engine performance began to falter - "What are you going to do about it?"

Well I still had PARTIAL POWER, and 1,500 feet, so I decided to continue toward the home field. and as we slowly lost altitude, and as the wind was light, I decided to do a straight in downwind approach and landing. Even though the instructor at this point pulled the throttle back completely, it worked very well. He said later he was sure I would have gone for a circuit to land into wind, so I passed the check ride.

How many instructors in the UK cover the danger of incorrect action when faced with a partial power problem? Is it part of the sylabus?

Genghis the Engineer 15th Jun 2013 23:04


How many instructors in the UK cover the danger of incorrect action when faced with a partial power problem? Is it part of the sylabus?
It isn't on any syllabus, but it's worth knowing. I generally mention it to my students - as it's something I've hit myself, but am on shaky ground insisting that they see it in the air, unless they ask to, because it's not on the syllabus and it's their money I'm spending.

G

fin100 15th Jun 2013 23:45

I never even thought of attempting a downwind turn to land until I got a check out at KTMH where the only possible efto landing was in the bay. I was given a engine failure and told to turn around - the month before an efto landing in the bay ended with two drowned.

Admittedly, we had got to 500ft and the turn was almost aerobatic steep turn nose down but it was more than possible and even if a hard rapid landing resulted if it was under control it would be survivable.

The point here is that you can practice this a height and in safety. There are places like this and EGHI for example where there is nowhere to go on 20 and the ability to carry it out safely and to know at what height you can do it from is worth knowing.

Its not something a rookie should try but as skill builds it could save your life - but baldly executed will kill you

Agaricus bisporus 15th Jun 2013 23:59

Turning back is a no-no in most aircraft as the angle of climb is such that there is simply insufficient altitude to make the turn and then reach the field. A turn uses a great deal of height and remember it isn't just 180 degrees to return to the runway. 180 degrees only takes you to a line the radius of your turn displaced, and that isn't likely to be much help. The turn has to be substantially more than 180' and then reversed so its going to be more like 230 minimum.

And by the time you realise you ain't gonna make it back you're completely bggered, too low and heading into the scenery downwind with no choice of where to go, stretching the glide in a downwind turn and.........guess what! That's the simplest formula there is for spin, crash, burn, die. Don't do it!

But I thought everyone knew never to turn back? Surely this is drummed into every student?

mad_jock 16th Jun 2013 05:52

it is if they have been trained by a Brit instructor that was trained in the UK from the word go.

The ones that did their PPL in the States its a different matter. There be alligators off the end of the runway etc.

Some of them myself included only learned how to do the PFL circuit during the flight instructors course.

And these guys will bring the subject up instead of just telling them that always go straight ahead. This then puts the idea into peoples heads.

There was quite a good youtube video on here I think of an EFATO and you can see the height drop increase as soon as they turned towards a likely crash spot and that was only 5-10 degs of bank.

mary meagher 16th Jun 2013 10:28

Genghis, if it isn't on the syllabus, surely it should be? if we take into account the Australian study... Who decides these things in the UK?
Could you send me a pm? I have another question .....

Mary

mad_jock 16th Jun 2013 10:35


Who decides these things in the UK?
Nobody, its all EASA. And with them the paper work is more important than standards of instruction or syllabus.

As long as your SMS system is hunky dory and you have manuals on everything from flying an aircraft to going for a pee your sorted.

The examiners are meant to do the quality side of things. But apparently most of the good uns are fed up with the cost and ballache of maintaining the privilege. And will be retiring when they are next due.

Genghis the Engineer 16th Jun 2013 13:37


Originally Posted by mary meagher (Post 7894652)
Genghis, if it isn't on the syllabus, surely it should be? if we take into account the Australian study... Who decides these things in the UK?
Could you send me a pm? I have another question .....

Mary

In instructional terms, I am somewhere very near the bottom of the food chain - there may be people here in a position to change the syllabus, but I don't think I'm one of them in this regard. However, I believe that there's a panel of examiners for each of the aircraft classes, all overseen by CAA? I think that with EASA the SEP panel (if that's what they're called) must find it much harder to change things now, but they must have a route to recommend things.

I'm unable to send or receive PMs at present for innocent but irritating historical reasons - but by all means drop me an email via the site. If that doesn't work, boffin (at) engineer (DOT) com will get me.

G

Tupperware Pilot 17th Jun 2013 06:49


If the engine failure was preventable then that is the root cause and the pilot's decision is a lesser factor.
I have to agree with this........There are two issues here! Engine then (and in that order) the turn!


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